Voltage Harmonic Reduction of Cascaded H-bridge Multilevel Inverter Based on SHEPWM by Using Optimized Immune Algorithm

The utilization of Selected Harmonic Elimination Pulse Width Modulation (SHEPWM) technology poses a significant challenge in addressing nonlinear equations due to its inherent complexity. To tackle this specific issue, this paper integrates the Immune Algorithm (IA) with SHEPWM. The IA, implemented using MATLAB, was employed to compute the modeling results for qualified switching angles. The simulation outcomes demonstrate that the application of IA in SHEPWM surpasses other algorithms in terms of Total Harmonic Distortion (THD) reduction and the Fast Fourier Transform (FFT) of line voltage in eliminating harmonics of a cascaded H-bridge multilevel inverter. This superiority arises from its enhanced performance in convergence rate and its ability to address local optima.